TOPIC:

Worked out a 4 part chassis, or 3 parts  considering the last one is an addon...


And that should print on one single plate in 8 hours on my X1C (PLA - it would be longer with PETG or ABS)...


The way I broke down the chassis was basically to try to obtain the better finish possible on the visible faces... I will have to test print this at some point...

I said that I would test a print to see the result...

The parts once the support were removed (and they were pretty easy to remove).



There is not much area where you can really see issues...


And assembled it gives this (and I just noticed looking at the pics I forgot to remove some supports on the reprinted key (0.2 mm tolerance as 0.1 was a bit too tight).




Dims are right and everything looks pretty good...


It seems I can be very happy with the result

Somehow, CAD phase 2 of the project is almost finished, and parts are ready for the final test... That said, it's a long time i'm eyeing a Hunter on ebay, and I pulled the trigger on Saturday... It arrived today

This is a tiny guy 1/32. and it was never thought to be remote controlled...


Time for CAD extended time! Let's try to do something out of this . I just order some tiny servos (super micro size), esc and rx. I'll look forward to find a battery as well very soon... And yes, my real target is to try to make a RC Hunter 1/32, and ideally fully printable (SLA resin or FDM). Not sure I'll keep the suspensions, I need to think about this, and there might be multiple iteration of this

Today, a few elements arrived.
I had already a mini servo sitting in my stuff (an order mistake at some point, but the data says it is powerfull enough for a car, I just way the good occasion to use it - spoiler : it won't be for this project).


It is small, but not small enough for 1/32. it would work good to make a 1/20 car... I have a smaller size servo on order, not sure when it will arrive, but i'm looking forward for it...


ESC and RX should not be much issue, on the other side...


Saying this, in the event the micro sized servo doen't work, I can probably target a 1/20, 1/24 or 1/28 Hunter (in anycases, I'm able to print a body shell mould (and possibly a bodyshell as well - even in colors eventually), and that should not be much a problem, and would probably easier for the battery as well...

Before moving on the target, we need to understand first if it is possible to print an universal joint in place and what tolerances are required for this. I first designed a universal joint around 1/2 of the original Hunter universal joint...


Next activity is to try to print it and play around with the tolerance to see if feasible...


And my 2 first tests were unsuccessful... It PLA, it doesn't help, and the print orientation neither... But we need to understand how interlocking can work before doing any optimsations...


I guess I will have many 10 mins print today for this...

3 semi-successfull prints. It always split at the same place, and suprisingly not parallel to the printing plan, but perpendicularly to it. The reason is because of tolerances in this situation. The one side I was expecting to break easily works perfectly as soon as you have more than .15 tolerances...

Basically, if we rotate the printing plan of 45° and make sure that the starting point of the cross member is supported that should work fine. I reviewed the design to add material which I intend to cut post printing.


And the test print is 100% success!


This means : Rear suspension is possible. I'm now thinking about scale : the optimal option seems to be 1/20 (scale 1/2 compared to the original Hunter), as screws and nuts are probably the easier to source in those dimensions, and it has the advantage of allowing for more material than lower scale.
 

The micro sized servo is arrived... It's really really really small


I will need to model this guy first and then think about the work to come... It may be very well suitable for a 1/32 size Hunter (without suspensions in the case I go for 1/32)...

Test your servo. My first one was dead same if it was new.

I got 2 and both are working properly...

To start working, we need to have the dimension right... So I put the two servos in CAD (it's a five minutes job, ad it will allow to work this out easily)...
Digging in the smaller size, I need to understand a bit better about gears printing in very small module.
I have the Marui gear set working in 0.8 (almost 32dp). Printing this scaled at 50% would probably give some indications of feasibility at 64dp (I may even use the Marui gearset scalled at 50% to make a 1/20 Hunter if it is workable). I put the gearset in Bambustudio, scaled it at 50% and printed it right in 0.08mm layer thickness, with tree supports and 100% infill.
Here is the result (with a Super Wheelie idle gear and not a Hunter one)
I used filament trimmed at the right length for the small bevel gear axis...
And it seems it is viable . I check and it works... I may need to review some posts of one of my friend about printing gears at it might be even usefull here...